• Natural Product Sciences
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• v.6 no.4
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• pp.193-198
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• 2000

Phytochemical study of the constitutive polyphenolics of the flower aqueous alcohol extract of Tamarix tetragyna was carried out. The new sulphated flavonol, quercetin 3',4'-dimethyl ether $3-O-KSO_3$ as well as the new natural galloyl glucose, $2-O-galloyl-({\alpha}/{\beta})-^4C_1-glucopyranose$ were isolated and characterized. The known sulphated flavonols, kaempferol 7,4-dimethyl ether $3,5-di-O-KSO_3$, quercetin 7-methyl ether $3,3',4'-tri-O-KSO_3$, quercetin 7,4'-dimethyl ether $3-O-KSO_3$ and quercetin $3-O-KSO_3$ and the known sulphated phenolics, isoferulic acid $3-O-KSO_3$ and ellagic acid 4,4'-dimethyl ether $3-O-KSO_3$ were also separated and identified. The structures were established by conventional methods of analysis and confirmed by $^1H-,\;^{13}C-NMR$ and negative ESI-mass spectrometry. 2D-homonuclear chemical shift correlation NMR experiment was applied for the new natural galloylglucose.

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1409-1412
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• 2014

Sex hormones are important metabolites in vertebrates' development and reproduction. For rapid screening sex hormones, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is one of the promising analytical platforms, but MALDI MS faces many challenges in detecting steroids such as low ionization efficiency and matrix background interference. One potential strategy to overcome matrix interference in the low m/z region is using a cyclodextrin (CD)-supported matrix for steroid analysis since CD-supported matrixes are known to effectively suppress matrix-related ion signals. In this study, we aimed to find the optimal CD-supported matrix for the analysis of the nonderivatized sex steroids. Our results showed that the ${\alpha}CD$-supported 2,5-dihydroxybenzoic acid (DHB) matrix efficiently ionized all three major classes of sex hormones, estrogens, androgens, and progestagens, with low or no matrix background and also with high sensitivity. In addition, the ${\alpha}CD$-supported DHB matrix mainly generated molecular ions or protonated ions of sex hormones, and this enabled us to obtain information-rich tandem mass spectra which potentially lead to unambiguous identification of steroid species from complex metabolite mixtures.

• Journal of Radiation Protection and Research
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• v.18 no.1
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• pp.37-51
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• 1993

A standard radon chamber and a radon generator adjusted by ventilation system which had used in this research were assumed to calculate theoretically the concentration of radon progeny using Jacobi model theory. On the one hand, the filter sampled from the radon standard chamber and the radon generator was measured and analysed by the alpha spectrometry method. It is clear that measured result shows a good agreement with theoretical result. Therefore, it is observed that this research can made a great contribution to more accurate internal dose assessment by alpha emission of radon progeny in indoor radon environment, and fast individual measurement and determination of concentration for radon progeny.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.10
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• pp.1416-1423
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• 2013

The metabolomic profile of the anaerobic fungus Piromyces sp. F1, isolated from the rumen of goats, and how this is affected by the presence of naturally associated methanogens, was analyzed by nuclear magnetic resonance spectroscopy. The major metabolites in the fungal monoculture were formate, lactate, ethanol, acetate, succinate, sugars/amino acids and ${\alpha}$-ketoglutarate, whereas the co-cultures of anaerobic fungi and associated methanogens produced citrate. This is the first report of citrate as a major metabolite of anaerobic fungi. Univariate analysis showed that the mean values of formate, lactate, ethanol, citrate, succinate and acetate in co-cultures were significantly higher than those in the fungal monoculture, while the mean values of glucose and ${\alpha}$-ketoglutarate were significantly reduced in co-cultures. Unsupervised principal components analysis revealed separation of metabolite profiles of the fungal mono-culture and co-cultures. In conclusion, the novel finding of citrate as one of the major metabolites of anaerobic fungi associated with methanogens may suggest a new yet to be identified pathway exists in co-culture. Anaerobic fungal metabolism was shifted by associated methanogens, indicating that anaerobic fungi are important providers of substrates for methanogens in the rumen and thus play a key role in ruminal methanogenesis.

• Transactions on Electrical and Electronic Materials
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• v.3 no.3
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• pp.29-33
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• 2002

A procedure was developed for preparing bulk carbon nitride crystals from a polymeric $\alpha$ -C$_3$N$\_$4.2/ at high pressure and temperature in the presence of seeds of crystalline carbon nitride films prepared by a high voltage discharge plasma combined with pulsed laser ablation of graphite target. The samples were evaluated by x-ray photoelectron spectroscopy (XPS), infrared (IR) spectroscopy, Auger electron spectroscopy (AES), secondary-ion mass spectrometry (SIMS), scanning electron microscopy (SEM) and x-ray diffraction (XRD). Notably, XPS studies of the film composition before and after thermobaric treatments demonstrate that the nitrogen composition in $\alpha$ -C$_3$N$\_$4.2/ material initially containing more than 58% nitrogen decreases during the annealing process and reaches a common, stable composition of ~45%. The thermobaric experiments were performed at 10-77 kbar and 350-1200 $\^{C}$.

• Analytical Science and Technology
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• v.15 no.6
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• pp.574-579
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• 2002

A sensitive and easy high performance liquid chromatograph (HPLC) / electrospray ionization (ESI)-mass spectrometric (MS) method has been developed for the quantitative and qualitative analyses of acarbose and its metabolites. After plasma samples were simply filtered with a syringe filter, the filtered plasma was analyzed by LC/MS. The standard calibration curve for acarbose was linear ($r^2=0.9963$) over the concentration range $0.1{\sim}10{\mu}g/m{\ell}$ in plasma. The metabolite component-I and II, which were metabolized by the ${\alpha}$-amylase and ${\beta}$-amylase, were found also by in vitro incubation. The developed method can be utilized to study acarbose and the other carbohydrates.

• Journal of Electrochemical Science and Technology
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• v.10 no.3
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• pp.257-270
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• 2019

The inhibition performance of sodium gluconate (SG), cetyltrimethylammonium bromide (CTAB) and their mixture (SG/CTAB) on the corrosion behavior of ${\alpha}$-brass in 0.5 M $H_2SO_4$ solution has been investigated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), Scanning Electron Microscope with Energy-Dispersive Spectrometer (SEM-EDS), Inductively Coupled Plasma Spectrometry (ICPS) and molecular dynamics (MD) simulation techniques. The results reveal that SG with 5ppm CTAB, noted SG/CTAB, acts as a good corrosion inhibitor and its inhibition efficiency reached 89% after 24 h immersion in sulfuric acid solution, but slightly decreased at higher temperatures. The polarization curves displayed that SG/CTAB acts as a cathodic-kind inhibitor. Electrochemical impedance spectroscopy (EIS) studies revealed that the addition of 5ppm CTAB to different concentrations of SG considerably increases the corrosion resistance of ${\alpha}$-brass. The SEM-EDS and ICPS analyses support the experimental results. Further, molecular dynamics (MD) simulations were used to understand the adsorption profiles of SG/CTAB on Cu(111) and Zn(111) surfaces.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.3
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• pp.189-198
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• 2006

Objective: We previously described that Diva is highly expressed in matured metaphase II (MII) oocytes compared to immature germinal vesicle (GV) oocytes in mouse. We report here that the expression of Diva transcript as well as protein is oocyte-specific. To elucidate its physiological role in oocyte, the binding partner(s) of Diva has been identified by using immunoprecipitation (IP) followed by Mass Spectrometry. Methods: NIH/3T3 cells were transiently transfected for 24 h with either empty vector for control or FLAG-tagged mouse Diva construct, and IP was performed with anti-FLAG antibody. The immuno-isolated complexes were resolved by SDS-PAGE on a 12% gel followed by Coomassie Blue staining. For in-gel digestion, 15 bands of interest were excised manually and digested with trypsin. All mass spectra were acquired at a positive reflector mode by a 4700 Proteomics Analyzer (Applied Biosystems, Framingham, MA). Proteins were identified by searching the NCBI nonredundant database using MASCOT Peptide Mass Fingerprint software (Matrixscience, London). Results: Diva-associated complexes were formed in FLAG-tagged mouse Diva-overexpressed NIH/3T3 cells via IP using anti-FLAG-conjugated beads. Among the excised 15 bands, actin and actin-binding proteins such as tropomyosin, tropomodulin 3, and ${\alpha}$-actinin were identified. Binding between Diva and actin or tropomyosin was confirmed by IP followed by Western blot analysis. Both bindings were also detected endogenously in mouse ovaries, indicating that Diva works with actin and tropomyosin. Conclusions: This is the first report that immuno-isolated Diva-associated complexes are related to actin filament of the cytoskeletal system. When we consider the association of Diva with actin and tropomyosin, oocyte-specific Diva may play a role in modulating the cytoskeletal system during oocyte maturation.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.273-279
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• 1999

Forty plants used as tea materials were chosen for determining the contents of total phenolics, selenium (Se), ${\beta}-carotene$, ${\alpha}-tocopherol$ and ascorbate. Total phenolics and ascorbate contents were analyzed colorimetrically. The Se contents were measured by hydride-atomic absorption spectrometry. The contents of ${\beta}-carotene$ and ${\alpha}-tocopherol$ were simultaneously determined by high performance liquid chromatography using separate detectors, UV for ${\beta}-carotene$ and FL for ${\alpha}-tocopherol$ analyses. The contents of these antioxidants were as follows (per 100 g dry plant); Contents of total phenolics in green tea leaf, black tea leaf, oolong tea leaf and instant coffee were about 7 g and the Se contents in corni fructus and arrowroot were found to be about $4{\mu}g$, which were the highest among all plants used. Contents of ${\beta}-carotene$ in eucommiae cortex, persimmon leaf and green tea leaf were 8587, 6222 and $3652\;{\mu}g$ respectively. The persimon leaf contained the highest ${\alpha}-tocopherol$ content (33 mg) and then followed by eucommiae cortex (26 mg), green tea leaf (16 mg) and black tea leaf (13 mg) in order. Ascorbate contents were found to be high in green tea leaf (199 mg) and black tea leaf (117 mg).

• Korean Journal of Medicinal Crop Science
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• v.22 no.3
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• pp.188-195
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• 2014

This study was carried to investigate the effect of illite addition on the growth, bioactive components and volatile compounds of leaf on Saururus chinensis Baill cultivation in greenhouse. Illite addition on Saururus chinensis Baill cultivation resulted no significant effects on the aerial part. However, the root part was highest in 5% illite addition group. Crude oil and ash amount increased as illite additives was increased. Ca of inorganics and free sugars contents were highest in 5% and 20% illite addition, respectively. Hyperoside and isoquercetin of available component on leaf were highest in 5% illite addition group, 4.02mg/g and 4.31mg/g, respectively. The volatile compounds in Saururus chinensis Baill leaf cultured with illite addition amounts were isolated by solid-phase microextraction fiber (polydimethysiloxane $65{\mu}m$) and identifed by gas chromatogtaphy mass spectrometry. As the results, the 22 volatile compounds were identified from in Saururus chinensis Baill leaf and major volatile compounds were the ${\alpha}$-cadinol (18.50%), myristicin (16.46%), methyl-9-methyl-tetradecanoate (10.22%), and ${\gamma}$-muurolene (9.75%). Especially, the content of ${\alpha}$-cadinol was highest in 5% illite addition group and ${\gamma}$-muurolene on overall illite addition group was lower than no addition group.